Crooked hole indicator



Jan. 31, 1933. W, ELLlOTT CROOKED HoLENDIcAToR Filed oct. 1, 1929liatented dan. 3l, lg3d` .mrs

R00 HOLE ENDIICATUR Application led october l, 3.929. Serial No.396,552.

rlhis invention relates to indicating apparatus to be used by welldrillers. llt should be distinguished from apparatus such as'has beenused for surveying a well after it is drilled to indicate theinclination or dip of the well at dierent points in its depth.

rlhe present invention concerns a device which is intended to be carriedin the drillstring near the bit for the purpose of indicating to thedrillers when the hole starts to go crooked. y

The general object of the invention is to provide a simple device or`this purpose 5 which can be carried inthe drill-string near the bit,and which can be operated lat will when desired to set it in anindicating position, indicating the inclination of the axis of thedrill-string. One of the objects of` the 2@ invention is to constructthe apparatus in such a way that it can be actuated by differentagencies.-

A further object of Vthe invention is to provide a device of this kindwhich .will not interfere with the passage of circulating iiuid past it,but which nevertheless, if desired, can be operated by uid pressure suchas could be developed in the circulating iiuid.

Further objects of the invention will ap.- 3@ pear hereinafter.

The invention consists in the novel parts and combinations of parts tobe described hereinafter, all of which contribute to produce an eicientcrooked hole indicator.. 'Y

A preferred embodiment of the invention is described in the followingspecification, while lthe broad scope of the invention is pointed out inthe appended claims.

ln the drawing: A

Figure l is a vertical section'through the device and showing a shortportion of a drillstring in which the device is placed.

' This view shows the indicating apparatus in its normal positiomVFigure 2 is a view also showing the yapparatus in longitudinal section,the upper portion of the view being shown in elevation.

This view shows the apparatus in an inclined position such as itwouldhave in a crooked portion of ahole being drilled, and illustratesthe apparatus inits set or actuated position. .Figure 3 is a horizontalsection .taken about on the line 3-3 of Figure l and furtherillustrating details of the preferredembodiment of the invention.

ltligure l isa vertical section taken through the lower end of thedevice and illustrating another embodiment of the in- @0 dicating memberwhich may be used as a Y part of the device. i

Figure 5 is a vertical section with some parts broken away upon asmaller scale and illustrating an embodiment of the invention in whichthe recording member is placed above the directional deviceinstead ofbelow it. v y

Before proceeding to a detailed description of the inventon, it shouldbe derstood that it employs asv an kelement of the combination adirectional device, such as a plumb-bob, which is carried' in such a waythat it is free to move so as to maintain itself constantly in a certainrelation. 75

Any device of this nature can be employed, but for simplicity l preferto employ` a plumb-bob which is mounted in such a way that it constantlymaintains itself with its axis in a substantially vertical position.This S0 directional device is mounted in the casing of the device insuch a way that it can cooperatev with an indicating member. Normallythe directional deviceor plumb-bob is out of cony tact with theindicating member, but adjacent 85 to it. ln the normal position of thedevice, Y when the hole is straight, the plumb-bob is in a position suchthat its axis coincides with the axis of the tool string and withthecentral axis of the indicating member. llt the hole being drilled startsto deviate the axis of the tool string and the casing of the instrumentwill become inclined, but the plumb-bob i will maintain itself with itsaxis vertical. When the parts are in this relation, l develop a5 arelative movement between the indicating member and the plumb-bob whichbrings them together, thereby forming an indication, or mark, by theplumb-bob on the indicating l member. This mark will be 0E the center of100 the indicating member, and the number of degrees that it is oif fromthe center will indicate the inclination of the crooked portion.

y ferial, but could be formed of any material which would operate toengage the point of the plumb-bob and hold it in a relativelyv fixedposition. For this purpose I might employ a punctural diaphragm of anysuitable material, or a diaphragm of wire gauze of line mesh.

The contact between the plumb-bob and the indicating member or elementcan be accomplished in any desired way, for example, by a down-j ar ofthe instrument such as would cause the point of the plumb-bob to strikethe indicating element; or if desired, the contact between the plumb-boband the indicating element may be accomplished by hydraulic pressure aswill be described hereinafter. Where the indicating member is of such anature as to produce a permanent mark when the plumb-bob strikes it, itwill not be necessary to hold the plumb-bob in contact with theindicating member, but if desired, I may employ detents which .operatewhen the plumb-bob is brought into contact with the indicating member tomaintain it in its position of engagement. In other words, I may providemeans for holding the plumb-bob relatively xed in the casing in theposition which it had when the device was operated to indicate thedegree of inclination of the hole.

In the preferred embodiment of the invention, I provide a casing 1,which is preferably of tubular form and attached at its upper end bymeans of a threaded collar 2 in the lower end of a section 3 of thedrill-string. Below this point the drill-string section 3 is providedwith threads 4 to receive the upper end of another drill-string section5 which may' be the drill collar or attached to the drill collarcarrying a drill bit of any type, for example, a fish-tail bit. Thiscasing 1 carries the directional device or plumb-bob mounted in such away that when the device is actuated by any suitable means it will comeinto engagement with a recording or indicating member. For this purposeI prefer to provide a movable carrier in the casing 1 which is capableof being moved to effect a relative movement Mtween the marker, orplumb-bob, and the indicating member. In

the present instance, the carrier is in the form of a piston 6 mountedto slide in a barrel 7 formed in the lower portion of the casing 1 andbelow a fixed head 8 that is attached in the tubular casing, therebyforming a water chamber 9 in the casing above the head 8. The piston 6is provided on its under side with means, such as a central post 10, forsupporting a plumb-bob 11. This plumb-bob is supported on the post bypivotal means (see Figure 3) providing two pairs of pivot screws, 12 and13, in alignment with each other to attain the effect of a gimbal joint,enabling the plumb-bob to move freely and maintain itself with its axisin a vertical position.

Cooperating with the plumb-bob, I provide an indicating element 14. Inthe present instance this indicating element cooperates with the point15 of the plumb-bob which is at the lower end of the plumb-bob, and thispoint 15 is normally adjacent but out of contact with the indicatingelement 14. This indicating elementy 14 is mounted in a fixed positionin the lower end of the casing 1 and maintained in position by screwingin a detachable head 16 secured by threads to the lower end of thecasing 1. The device is preferably provided with means, such as a coilspring 17, for normally holding the plumb-bob and the indicating element14 out of contact with each other. This spring is preferably mountedunder the piston 6 so as to hold it in an extreme raised position.

A device having lthe parts described above can be operated by a down-jarwhen desired, the weight of the plumb-bob and piston operating tocompress the spring 17 and enable the point 15 of the plumb-bob toengage and mark the indicating element 14. If it is desired to retainthe plumb-bob in engagement with indicating element 14, this may beaccomplished by providing a plurality of detents 18, which may be in theform of leaf springs/attached at their lower ends to the inner face ofthe wall of the piston 6, theirv upper ends normally resting against theside of a neck 19 projecting down from the head 8.

If the piston 6 moves downwardly, these detents 18 will snap inwardlyunder an annular shoulder 20 on the neck, and thereby prevent return ofthe piston and the plumbbob to their normal elevated position. In thisway the plumb-bob will be maintained in contact with the indicatingelement.

The device is preferably constructed so that all of the parts can'be putinto the casingv from below, for which purpose the spring 17 is mountedin a spring barrel 21, with an internal shoulder 22 upon which 'thespring seats. In this way a large opening 23 is4 formed, at the lowerend of the barrel to permit lateral swinging movement of the plumbbob(see Figure 2). Below the spring barrel 21 a distance ring 24 isprovided which fills neeaeia the space between the lower end oil thespring barrel and the indicating member 1.4i. [is illustrated, the edgeof the indicating member is clamped between the plug 16 and the lowerend of the ring, or errule,

The device is preferably constructed so that it will not interfere withythe use of circulating water in the regular way. F or this purpose thewall of the water chamber 9 is provided with'a plurality oi water ports25, which preferably incline downwardly to ward the annular chamber orwater passage 26 that is formed in the tubular drill-string section 5lso that the circulating water can pass down around the casing 1.

'lhe head 8 is provided with means tor ad initting iiuid pressure intothe casingl above the head oi the piston o. For this purpose a centralopening or port 27 is formed in this head. ln order to prevent thepressure o' the circulating water above the piston t5 irom actuating itbefore desired, a plurality oi vents 28 are" provided openingcommunication between the annular space 26 and the interior ci thecasino i below the piston head. lr the pressure` or the circulatingwater is gradually built up, water will till the interior of the casingl below the piston, and the pressure above and below the pistonwillbecome equalized. The'water below the piston surrounds the plumb boband dampens its relativenioveinent. 'lhese vents 28 also enable thepiston 6 todae advanced it the pressure oi the circulating water iscluiclrly increased, by permitting the out-tlow oi the water in vcasing1 below the piston. ln this connection it shouldbe understood that thepressure oi the circulating water is suddenly in# creased, there wouldbe sutlicient pressure on the upper side of the piston to insure itsdownward movement. .ln other words, uvder these conditions the pistonwould advanced by a diderential pressure action. n

lt lwill be obvious, however, Tt iii desired the device could beconstructed in a way that it could be operated directly by pressureadmitted only in one side or the piston..

instead of employing a recording or actu-l member 1lio'' yieldingmaterial employ an i dicatmg element 2% f see termed wire gauze oi meshor any other suitable material which could engage the pointo2 theplumb-bob 30 (see lligure il) to hold same in a relatively linedposition.

The plug iti-may have angular or heir: agoiial soclret Si to enable itto'ioe screwed into place hy means of a wrench. e

rlhe mode oi operation ci the apparatus will now be briefly described.it a yielding material, such as lead, is employed to torni theindicating element 1e, it will not be necessary to provide the devicewith the detente 18 because the point oi the plumb-bob will form a smallconical impression in the upper face of the lead element or diaphragm14. However, as it may be convenient to use the same lead element againand again, impressions made at diderent times might be con- `fused witheach other. For this reason it is desirable to provide the detente 18.l

ln using the device, a down-jar will cause the point-15 of the plumb-bobto engage the indicating element 1d and mark it. When the tool string ispulled, the position ot this mark will indicate the inclination of thetool string at the time the mark was made.

lt the deents 18 are present, they will lool: the plumb-bob inengagement with the indicating element lli desired, the recording diskmay be placed above the plumb-bob instead of below it, see Figure 5 inwhich 32 represents a plumb-bob mounted on a gimbal joint 33 and havinga sharp pin 3d projecting upwardly on its axis. Above the pin within thecas/ingV 35 oi the instrument a recording dish 36 is mounted. rlhisrecording disk is carried on a movable piston 37 that may be moved downso as to compress the spring 38 either by jar or by fluid pressureadmitted Vto the, upper side of the head 37 through a port 39. 'l`hespring 38 normally holds the head 3'? elevated so that the recordingdisk is out oi contact with the point or@ the pin. lf desired, springslO similar to the springs 18, may be employed to hold the recordingmember 36 in contact with the pin 34.

'li it is desired to operate the' device by fluid or hydraulic pressure,this can be aclll@ complished by suddenly raising the pressure of the`circulating water. rlVhis will produce a preponderance oi pressure onthe upper side o' the piston or carrier 26 which' will cause theplumb-bob to move down so that its pointwill engage the indicatingelement.

li desired, a viscous fluid, such as oil, could he employed in theylower end oi vthe device as indicated by the dotted line in Figure 2QThe function et this Huid would be to dampen"`7 the swinging movementsoi the plumb-boh and thereby insure an. accurate lacing oif the marit onthe indicating memlt is understood that the embodiment et the inventiondescribed herein is only one voiE the many embodiments this inventionmay take, and do not wish to be limited in the practice of theinvention, nor in the claims to the particular embodiment set forth.

`llclaimz 1. ln a crooked-hole indicator ior well drillers, to cooperatewith liquid pressure means at the mouth oi .the well, the combination ofa casing having means for attaching the saine to a drill string, andhaving a plumb-bob'chamber, a plumb-bolo with pivetal means forsupporting the same in the plumb-bob chamber so that the plumb-bob isfreely movable to maintainitselii with its uit l llt@ iat i axis in asubstantially vertical position, an indicating member carried' withinthe plumbbob chamber to cooperate with the plumbbob, means forconducting liquid under pressure from the drill string into theplumb-bob chamber to surround the plumb-bob and dampen its swingingmovements, and a piston carrying the plumb-bob and operating` upon asudden increase of pressure, to move the plumb-bob into engagement withthe indicating member while the casing is located at the crooked part inthe hole.

2. In a crooked-hole indicator for well drillers, to cooperate withliquid pressure means at the mouth of the well, the combination of acasing having means for attaching the same to a drill string, and havinga plumb-bob chamber, a plumb-bob with pivotal means for supporting thesame in the plumb-bob chamber so that the plumb-bob is freely movable tomaintain itself with its axis in a substantially vertical position, anindicating member carried within the plumb-bob chamber to cooperate withthe plumb-bob, means for conducting liquid under pressure from the drillstring. into the plumb-bob chamber to surround the plumb-bob and dampenits swinging movements, and a piston carrying the plumb-bob andoperating upon a sudden increase of pressure, t0 move the plumb-,bobinto engagement with the indicating member while the casing is locatedat the crooked part in the hole, a fixed head in the casing above thepiston with a port therethrough for admitting the fiuid under pressurefrom above, to the upper side of the piston, said fixed head having anannular shoulder on its under side, and said piston having resilientmeans for engaging the annular shoulder when the piston movesdownwardlyto hold the plumb-bob in engagement with the indicatingmember.

3. In a crooked-hole indicator for well drillers to cooperate withliquid pressure means at the mouth of the well, the combination of altubular casing having a bore to communicate with the interior of thedrill string and having a fixed head within the `same with a porttherethrough, a drill string section surrounding the tubular casing forconducting liquid downwardly past the fixed head, said tubular casinghaving ports therein for enabling water to pass outwardly through thewall of the tubular casing above the said fixed head, a piston mountedfor movement in the tubular easing below the fixed head, and a springnormally holding the piston in an elevated position, a plumbbobsupported for free movement from the under side of the piston, so as toenable the plumb-bob to maintain itself with its axis in a verticalposition, an indicating member held in the lower end of the tubularcasing below the plumb-bob, said piston operating when the liquidpressure in the upper end of the said tubular casing is suddenlyincreased to force the plumb-bob downwardly and into engagement with theindicating member.

4. In a crooked hole indicator for well drillers, the combination of acasing having means for attaching the same to the drill string, anindicating member in the form of a diaphragm carried within the casing,a plumb-bob within the casing above the indicating member, pivotal meansfor supporting the plumb-bob so that it is freely movable to maintainitself with its axis in a substantially vertical position, saidplumb-bob having a point at its end lying adjacent said indicatingmember, a carrier for the plumbbob in the form of a piston-movable inthe casing, means for admittingfiuid underpressure to the upper andlower side of the piston operating so that when the pressure is suddenlyincreased, a differential pressure is developed greater above thepiston, for moving the plumb-bob into contact with the indiy eatingmember, and means for holding the plumb-bob thereafter in Contact withthe said indicating member.

5. In a crooked hole indicator for well drillers, the combination of acasing having means for attaching the same to a drillstring, anindicating member in the form of a diaphragm carried within the casing,a piston inovably mounted within the casing, a plumb-bob, pivotal meansfor supporting the plumb-bob from the piston so that the plumb-bob isfreely movable to maintain itself with its axis in a substantiallyvertical position, said plumb-bob having a point at its end lyingadjacent said indicating member, means for admitting fluid pressure tothe upper and lower faces of said piston including a relatively smallport for admitting the fluid to one side of the piston, so that when thefluid pressure is suddenly increased, a differential pressure isdeveloped, operating to move the piston in a direction to bring the saidpoint into contact with the indicating member while ..the casing islocated at the crooked point'in the hole, and detents carried by thepiston. with means cooperating with the same to hold the plumb-bob incontact with the indicating member.

6. In a crooked hole indicator for well drillers, the combination of atubular casing closed below to enable it to hold a motiondampeningliquid, a piston mounted for movement in the upper part of the casing, afixed head in the casing for limiting the upward movement of the piston,a plumb-bob with means for supporting the same from the lower end of thepiston for free movement laterally in the motion-dampening liquid,V aspring surrounding the plumb-bob, normally holding the piston in anelevated position the said means for supporting the plumb-bob neaaeiaenabling the plumb-bob to maintain itselio with its axis in asubstantially vertical p0- sition, and an indicating member held fixedin the lower end of the casing below the plumb-bob.

7. lin a crooked-hole indicator for well drillers, the combination of atubular casing, a piston mounted nfor movement in the upper part of thecasing, a spring normally holding the piston in an elevated positionwithin the casing, a fixed head in the casing for limiting the upwardmovement of the piston undei` the action of the said spring, a plumb-bobwith means for supporting the same from the under side of the piston forree movement, and enabling the plumb-bob to maintain itself with itsaxis in a substantially vertical position, an indicating member heldlixed in the lower end of the casing below the 'plumb-bob, said fixedhead having an annular shoulder on the same, and springs carried by thepiston and operating upon a downward movement of the piston, to engagethe annular Ashoulder and hold the piston down.

Signed at Los Angeles, Calif., this 3rd day of Sept. 1929.

WALTER lELLllTT.

